Posted on 03/08/2010 10:02:04 PM PST by neverdem
Temperature records gleaned from clamshells reveal accuracy of Norse sagas.
Oxygen isotopes in clamshells may provide the most detailed record yet of global climate change, according to a team of scientists who studied a haul of ancient Icelandic molluscs.
Most measures of palaeoclimate provide data on only average annual temperatures, says William Patterson, an isotope chemist at the University of Saskatchewan in Saskatoon, Canada, and lead author of the study1. But molluscs grow continually, and the levels of different oxygen isotopes in their shells vary with the temperature of the water in which they live. The colder the water, the higher the proportion of the heavy oxygen isotope, oxygen-18.
The study used 26 shells obtained from sediment cores taken from an Icelandic bay. Because clams typically live from two to nine years, isotope ratios in each of these shells provided a two-to-nine-year window onto the environmental conditions in which they lived.
Patterson's team used a robotic sampling device to shave thin slices from each layer of the shells' growth bands. These were then fed into a mass spectrometer, which measured the isotopes in each layer. From those, the scientists could calculate the conditions under which each layer formed.
"What we're getting to here is palaeoweather," Patterson says. "We can reconstruct temperatures on a sub-weekly resolution, using these techniques. For larger clams we could do daily."
It's an important step in palaeoclimatic studies, he says, because it allows scientists to determine not only changes in average annual temperatures, but also how these changes affected individual summers and winters.
"We often make the mistake of saying that mean annual temperature is higher or lower at some period of time," Patterson says...
(Excerpt) Read more at nature.com ...
The right sidebar has a link for this open access pdf. If this technique is valid, then we'll know if the Medieval Warm Period was global or just around the North Atlantic region.
Grasping@molluscs.
Uh, I would expect that warmer waters should favor the heavy oxygen isotope, as lighter isotopes would be driven off first as the waters warm.
Until they do away with their flawed philosophy they call science, its all more of the same.
Of course, doing that would likely cut into their grant monies.
When it comes down to money versus objectivity, money talks.
No doubt, it will be much easier to use this data to fit the theory.
Hurray for Pseudoscience!
More hocus pocus.
This is going to cost some clams!
Hurray for Pseudoscience!
How so? Isotope data are hard numbers, no?
Again I’m curious, does the story have it backwards about the isotopes and the water temperature? Water molecules containing heavier oxygens would be more reluctant to evaporate than their lighter counterparts. This means they would be favored at higher temperatures.
Also, what mechanism governs the mix of the isotopes? Is there some way of checking this? Otherwise our whole temperature scale could scoot up and down over time and we would not know it.
favored => favored to remain in liquid state, that is.
Also, what mechanism governs the mix of the isotopes? Is there some way of checking this? Otherwise our whole temperature scale could scoot up and down over time and we would not know it.
You have good questions. I have not read the pdf, just the abstract.
Technically interesting but I doubt this is very accurate for climate research. But scientists will love it ‘cause they get more money to squander. Climate research is a recession proof scam. A scam for all seasons!
Don’t take the word of money grubbing, grant obsessed scientists that this is accurate or useful in any way for researching historical climate. I have not read the pdf and I don’t intend to. Call me cynical
If the scientists didn’t keep this all closed up in their private hidey holes, there would be much better reason to believe their conclusions. There’s no better review than to allow the entire world to see what you’re doing.
And, there’s one problem right off the bat — joining together these decade-long lives of our little shelled friends at the bottom of the sea. If the data is too fuzzy it won’t even be possible to see back into the Medieval Warm Period.
The right sidebar has a link for this open access pdf. If this technique is valid, then we'll know if the Medieval Warm Period was global or just around the North Atlantic region.Really? Who gives a f*&% and why does it even matter?
Do you people really take this shit serious enough to regurgitate their drivel as a serious important subject with a straight face? Really?
Unfortunately for us, the anthropogenic globull warming affair has assumed proportions that we cannot ignore. This would be a way of checking up on a dodge that AGW proponents use to try to discount the historical and other evidence that suggests that the world was much warmer a millennium ago without any help from man. The AGW people claim it was warmer only in the places where we are looking, but it was colder elsewhere. If we can look in more places, this dodge could be eliminated.
Who cares! Let that taxpayer grant money flow! Laissez le bon temps roulez! Think of all the ships and crews to be paid. All that extra lab time and pay for the grunts. New hi-tech analytical equipment to buy and get kick backs for! Think of all the grad students and scientists being employed!
This would be a way of checking up on a dodge......
Get real! I doubt this method will be accurate or helpful. Don’t accept any grant proposals from grant grubbing scientists until verified then verified again.
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